The present invention relates to a motor vehicle which is equipped with a liquid-cooled internal combustion engine. The engine is cooled by a radiator through which there is a continuous flow of coolant, the radiator itself having first and second regions, the latter being serially connected, via a thermostatic valve, with the first region only when the coolant is above a predetermined temperature.
Arrangements of this type are shown, for example, in German Pat. No. 1,022,105 issued June 12, 1958 (first published Jan. 2, 1958) and German Pat. No. 1,027,083 issued Sept. 11, 1958 (first published Mar. 27, 1958), where the physical construction of the radiator is such that it is divided into two individual, separately identifiable components. Dividing the radiator into two separate components only one of which, namely, the one that is the first one upstream as considered in the direction of flow of the coolant, has the advantage that the internal combustion engine will have a relatively short warm-up time, because only a relatively small proportion of the total volume of the coolant in the system will be recirculated through the radiator. Only after the coolant has reached a predetermined temperature, which will be the temperature at which the thermostatic valve is set to respond, will there be flow of coolant through both the first and second radiator components, thus preventing overheating of the engine. In practice, the second radiator component, namely, the one which is not traversed by coolant during the warm-up time, will generally have a larger capacity than the first component.
Another advantage of providing two separate radiator components is achieved when, as is likewise described in the mentioned German patents, the first radiator component is used as part of the heat exchanger for the heater which serves to heat the interior of the motor vehicle. The reason for this is that in vehicles in which the entire radiator is used as the heat exchanger for the heater, it will take a relatively long time for the coolant to reach a temperature which will enable the heater to put out the amount of heat required to warm up the interior of the vehicle, because it takes a certain amount of time for the entire quantity of coolant to warm up. If, however, the radiator is divided into two components and only one of them is used as part of the heat exchanger, the amount of coolant flowing through it will be less than the total capacity of the cooling system and this, in turn, allows the reduced quantity of coolant to warm up more quickly. It will be appreciated that thanks to such an arrangement, the heat output of the heat exchanger, which is introduced into the interior of the vehicle either by a blower and/or by the ram air effect if the vehicle is moving, is available relatively quickly so that the interior of the vehicle can be heated up more rapidly than otherwise.
The above-described arrangement has the drawback in that it is relatively expensive to build and assemble a radiator having separate components, and it is, therefore, a basic object of the present invention to provide a radiator arrangement which, while taking advantage of the two-component concept, is structurally as uncomplicated as possible. Specifically, it is an object of the present invention to provide a way in which to utilize the two-component concept while making it unnecessary to provide two physically separate radiator components. Instead, the present invention provides a way in which to make use of a radiator which itself does not have any separate, interrupted tube systems, so that a major structural part of the radiator, which is the tubing system, can be mass-produced and can, in a manner of speaking, be cut to the desired length from a "band" of tubing.